Contemporary challenges for hospital epidemiology.

According to conventional wisdom, it is time for hospital epidemiologists to look beyond traditional infection control responsibilities and to shoulder an "expanded role," including quality assurance, risk management, and pharmacoepidemiology. Some see this as a matter of survival as the profession reacts to potent external forces that seek to curb the cost of health care while assuring quality service. Infection control specialists, it is argued, have the epidemiologic skills to measure adverse outcomes of hospitalization, adjust for confounding variables, and evaluate the impact of targeted interventions. Before embracing these new responsibilities, however, it should be noted that many hospital epidemiologists would require additional training in basic epidemiologic principles. Although hospital epidemiologists may seek a leadership role in hospital quality assurance and health policy research, they have generally not been innovators in these fields, even in some specific areas relevant to infection control. For example, while hospital epidemiologists have begun to consider severity of illness as a potential confounder in epidemiologic analyses, they have not participated in the development or validation of any of the most widely used indicators. For those hospital epidemiologists who wish to capitalize on their traditional background in infectious diseases, contemporary infection control provides numerous challenges. For example, the epidemiology of many common nosocomial infections, such as bacterial pneumonia in immunocompromised hosts, remains to be defined. Hospital epidemiologists need to incorporate a variety of sophisticated microbiologic methods into their practice to help them trace the spread of nosocomial pathogens. Finally, they should collaborate more closely with clinical and bench investigators in a number of areas, including microbial pathogenesis, immunology, and biotechnology.